Congressional wrangling over the stimulus package helped take the ideas of a national smart grid and utility decoupling out of wonky obscurity, but stopped short of mandating their implementation. Senate Majority Leader Harry Reid wants to go further, to bulk up the federal muscle behind a grid buildout. The Nevada senator told a gathering of political, business, energy and labor heavyweights in Washington, D.C., today that he plans to introduce an energy bill late this week that, if passed, would expand government authority for siting transmission lines. It would, he said, put an end to an era in which one state can “hold up forever something that needs to be done for the good of the country.”

More importantly, such a move would make it easier to build infrastructure for carrying energy from places with abundant wind, solar and geothermal energy resources to population centers with higher demand for electricity. He said the bill will be bipartisan, but did not disclose a Republican co-sponsor.

Reid revealed his timeline and scant but important details about the bill at the National Clean Energy Project summit, an event that has in attendance such influential figures as former President Bill Clinton (who called for Congress to pass a federal decoupling mandate), former Vice President and Kleiner Perkins partner Al Gore, Secretary of Energy Steven Chu, energy magnate T. Boone Pickens and House Speaker Nancy Pelosi. Asked in a press conference about potential resistance to the bill on the part of the National Association of Regulatory Utility Commissioners, a group of 253 state regulators, Reid said, “Whatever we pass at a federal level trumps all of that.”

Not everyone supports this route. VantagePoint Venture Partners VC and longtime environmental advocate Robert F. Kennedy Jr., for example, didn’t express flat-out opposition at today’s summit, but he wondered if three systems — one for the East, West, and Texas regions, respectively — might offer a more viable solution. Each of the three regions has a workable balance of renewable energy supply and demand, and the smaller scale could simplify negotiations.

But the real friction is expected to come from state regulators, according to Senate Energy and Natural Resources Committee Chair Jeff Bingaman. States that would get transmission lines but no energy (crossover states) have reason to worry about getting short shrift. Not so with Nevada — part of the reason Reid has championed the issue. He noted that his state has far more geothermal and solar resources than its population demands. “We can’t use it all,” he said. “We need to be able to take the energy where it’s needed.”

(For those of you who have raised the valid point in our comments section that distributed generation, such as residential solar power systems, can get going without such a massive investment, Gore added that long-distance transmission lines offer a way to transition off of faraway coal power plants, but could eventually be used to support distributed systems.)

Much of the resistance to a national grid stems from the issue of “exits” — in other words, where and how electricity gets dropped off along a transmission route. Here, the DOE may be able to help. Secretary of Energy Steven Chu said he plans to support development of advanced switches and industry-wide standards. With improved technology, off- and on-ramps along an interstate highway system for electricity would become more feasible, helping to bring crossover states on board. Chu clearly has the will. With fresh billions in his agency’s purse, he also has the means. Now Reid wants to give him the mandate.